Send Time Optimization in MailChimp

With the latest release of MailChimp, we’ve added the ability to optimize your send time. Within the send time scheduling section of the app you’ll find a recommendation hand-delivered to you from MailChimp’s Email Genome Project. It recommends the optimal send time out of the next 24 hours from the selected delivery date. The send time recommendation is determined by clicks, the idea being that your predicted time will maximize your click-through rate.

Send time optimization’s basic mechanics

At a high level, send time optimization looks at the send and click data for your specific list of subscribers and makes a recommendation based on their past engagement times.

But there are a few nuances that I want to make clear up front:

Since MailChimp has 4+ million users, we look globally at each email address’ engagement in deciding the best time to send to your list. Chances are the email addresses on your list receive email from other MailChimp users. That means that even if you’ve never sent to your list or only sent a few times, we can still provide a recommendation.

The recommendations are for a 24 hour period and change dynamically as new data rolls in across the MailChimp ecosystem, so recommendations will change over time.

The send time recommendation is weighted toward the most engaged readers on your list. After all, why would you want to optimize for the dead weight on your list that never opens?

The model doesn’t simply choose the time slot with the highest number of clicks, but rather a time slot with an excellent click-to-send ratio. A time slot can have a ton of clicks simply because it has a ton of sends, and that’s not a great metric.

Sends from previous time slots are factored into the calculation as well. For example, in the charts below, the send and click distribution is more preferable for a 6 p.m. recommendation in the second chart than in the first. Why? Because in the top scenario, there are plenty of clicks at 6 p.m., but since that’s when the email is actually hitting the inbox, the send time is driving the click time more than in the second chart. There, we’ve got a clear delay between send and click, implying that this is when subscribers are entering into the content to engage because it’s convenient for them. In both cases, 6 p.m. is naturally more preferable than 3 p.m., when there ain’t nothin’ going on.

Not ideal.Much better, thank you.

Give it a shot

Just because there is no global best send time to rule them all doesn’t mean there isn’t a best time for your list. And send time optimization helps you figure that out.

The feature is only available to paid accounts, but if that’s you, give send time optimization a shot and see how it performs versus your previous campaigns. But keep in mind, the primary driver of engagement for your list is you: your content, your industry, the list you’ve uploaded. Send time optimization is icing on an engagement cake—or icing on an engagement meatloaf if your list is hemorrhaging. If someone doesn’t want to open, they won’t open, regardless of delivery time. However, when someone wants to open, this model helps line up the send with their availability.

This looks great, thanks Mailchimps! I did a fair amount of A/B split testing, but I think your results may be way better to calculate.
Do you thinks this feature will be integrated in the autoresponders as well? I would love Mailchimp to decide what time is best to sent it to a fairly new subscriber.

Nothing’s impossible, though in its current incarnation, the tool looks at your entire list of recipients and calculates an “average” best time to send (and it looks at the best time in the next 24 hrs). All to say it’s not built for one-to-one, real-time messages. Not yet, anyway.

Hi Jason, Send time optimization is for monthly or pay-as-you-go paid accounts. If you’re currently a paid account and still not seeing it for some reason, would you mind reaching out to our support team at: http://mailchimp.com/chat and they’ll be happy to take a closer look.

My mistake, it is actually available in regular campaign but not in A/B split.

One further question, most of my subscribers are actually locating in different time zone quite unevenly around the globe. Dose this mean A/B feature tends to be more effective than optimal sending time in terms of increasing open rate? Or it is actually more complicated than my understanding?

Hi Jason, So this could be looked at and tested in a number of different ways, but I don’t believe there’s going to be one specific “right” answer. Keeping in mind that send time optimization is specific to click rate and not open rate, you might want to segment your list into a couple random segments (our segmenting tool – Hairball can help you there) and test send time optimization against time warp for example. You might actually find that even though you have a very geographically dispersed list, that there may be one or a few regions that are particularly engaged. If you’re looking at A/B vs Send Time Optimization, you’d be comparing single time behavior over aggregate past behavior when using A/B to determine send time. There’s certainly a case to be made for both options, but only testing against your list will be a good indication of which option might best work for you.

FYI the Simple Relevance integration does just that — sends individual emails to users based on their own individual behaviors. However, I believe it’s just for pure B2C eCommerce right now, but the concept is a killer one, and I’m sure the folks at MC and others will have this capability eventually as hyper-individualized marketing becomes more and more the norm.
Keep up the awesome work!

Hey KC, While it’s not available directly for RSS campaigns, you could setup a temporary campaign to the same user group in the future. Just make sure the recipients are all the same and set it up as a regular campaign. Once you get the recommended send time, you can just delete the temporary campaign and go back to your RSS and set it to that time going forward.